sequenceDiagram
participant U as User
participant L as LLM
participant C as Your Code
participant D as Live Data Source
U->>L: "What is NVIDIA's stock price?"
Note over L: I need live data — signal need
L->>C: (structured signal) fetch_stock_price("NVDA")
C->>D: API call / database query
D-->>C: {"price": 142.50, "timestamp": "2026-02-23"}
C->>L: tool result: $142.50
L->>U: "NVIDIA is currently trading at $142.50."